This invention relates to fifth wheel hitches. A common feature of fifth wheel hitches of various types which have been employed for decades is the use of one or more shiftable locking jaws to close the throat of the fifth wheel top plate. Two popular variations are set forth in expired U.S. Pat. Nos. 2,610,069 and 2,663,575 to Ketel. The structure in the '069 patent has the pair of pivotal jaws interengaged by special gear teeth. A locking plunger is shown to reciprocally slide into a position locking the two jaws closed. Another plunger arrangement for locking the two jaws is set forth in U.S. Pat No. 4,106,793 to Neff. It is common to have a pull handle interconnected to the locking plunger, to retract the plunger and thereby allow the driver to release the jaws from the kingpin. This release handle typically has a cam track and cam follower for shifting the locking plunger or dog.
U.S. Pat. No. 4,659,101 to Buckley discloses a fifth wheel hitch having a fixed jaw and a swinging jaw, with the swinging jaw including a closure finger projecting horizontally into the throat of the hitch so as to be engaged by the enlarged lower head of the entering kingpin for closure of the jaws. That fifth wheel hitch also has a locking plunger to retain the jaws closed and biased toward the locked position. The plunger is cammable to a release position by a slide cam plate. The adjustment mechanism for the plunger incorporates a wedge movable transversely of the hitch.